Air filter question.

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10 inch Terror
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Main scooter: Lambretta LI Imola 185
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Hi all, I am currently running my Imola with Mikuni TN28 and a smallish ram air filter, she runs nice abeit a tad rich as i'm still running her in. Anyway yesterday i decided to see how she went without the air filter on and, the engine bogs down badly anything over quarter throttle. Is this a bad sign? I am really paranoid of having an air leak and causing serious damage, could someone put my mind at rest or help me avoid a disaster. Any advice / comments very welcome. Thanks Pete
Scooteristi
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Removing the air filter CAUSES AN AIR LEAK!!!!
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mark
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what filter is it? i only ask because normally when you remove an air filter and run open mouthed you are allowing more air in so it will run leaner and you risk killing the piston( at least) but my camlam easy breathe filter made the bike run leaner not richer this was proven on the dyno at diablo and again i proved this by plug chops on the road with both open mouth carb and filtered carb.it wasnt a lot of difference but it was a difference
nelson pk
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Yep, filters will effect the jetting. As a general rule you will be running leaner when you take the filter off (i'm not doubting the above post but i think that would be quite rare) so if it causes a flat spot or bogginess (reluctant to come on the power) put the filter back on and jet more accurately when run in.
Either way , you will need to decide if you want to run with a filter or not and jet accordingly, it wouldn't be wise to jet it with the filter on and then decide to take it off. Even running with your side panel off will effect the jetting compared to running with it on unless you have a hole cut in the panel for the carb.
10 inch Terror
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Main scooter: Lambretta LI Imola 185
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Thanks for taking the time to reply gents. As jetting can be a minefield i've decided to let an expert set it up on a dyno. Thanks again Pete
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